The present invention pertains to an aircraft tractor without a tow-bar, comprising a chassis, which may be divided and whose front wheel axles are mounted on a front part and whose rear wheel axle journals are mounted on a rear part. The rear part is forked by a recess for receiving the nose wheel landing gear. The rear part is hinged to the front part via a single articulated axle that is parallel to the rear wheel axle. On this front part, possibly behind the articulated axle, a lifting platform is arranged at the front end of the chassis recess, wherein said lifting platform has a support surface for lifting up the nose wheel landing gear. The support surface slopes downward when the chassis is folded and is horizontal when the chassis is extended. Two mirror image tow arms are arranged at the rear end of the chassis recess. The tow arms can be moved both from a longitudinal position on each side of the recess (to provide a nose wheel gear path) to a transverse position for reaching behind a nose wheel gear, and in the forward direction. At least one nose wheel holder, which is arranged at the front end of the chassis recess above the lifting platform, is provided which can be moved in the rearward direction.
In a tractor of this class, which is known from DE-OS/PS 36,16,807 (Schopf/MAN), the lifting platform provided as a platform for receiving the nose wheel landing gear of the aircraft is connected rigidly to the front part of the chassis, and is designed, e.g., in one piece with the front part of the chassis. The two tow arms and the two corresponding holding arms, which hold down the two wheels of the nose wheel landing gear on the support surface of the lifting platform, are immobile in their temporary or permanent horizontal transverse position perpendicularly to the longitudinal axis of the tractor.
As a consequence of this arrangement of the lifting platform as well as the tow and holding arms (holders), one nose wheel is raised on one side and the load on the other nose wheel increases on the rigid lifting platform during a curving movement of the tractor. This occurs during turning or curving movement when the lifting platform has picked up an inclined two-wheel nose landing gear of an airplane being towed. When this occurs the grasping and holding arms, on one hand, and the nose wheels, on the other hand, perform relative movements, which are associated with great friction.
Another drawback is loss of a primary advantage of the prior-art tractor, according to which the nose wheel tires of the aircraft are not subjected to any unusual deformation either when grasped or when lifted, because the lifting platform creates a second bottom corresponding to the road surface, on which the nose wheels are flexed naturally, in the case of aircraft with inclined nose wheel landing gear.